This unit of work consists of five Word files covering Centre of Mass, Centre of Gravity, Stability, Moments, Equilibrium and the Principle of Moments. They require the completion of words, numbers and calculations by the student. The first file, of two pages, covers the concept of Centre of Mass, Centre of Gravity and Stability. It includes some questions on stability. The second file, of three pages, covers the concept of Moments, equilibrium and the Principle of Moments. There is an emphasis on how to set out calculations. The third file, of one page, has a worked example (with parts to be completed) of how to find the mass of a metre rule by experiment. Students can then do their own experiment and use the same method with their results. Lastly there is a question to check on understanding. The fourth file, of one page, is four more moments questions of increasing difficulty. The fifth and last file, of 1 page, is a Moments Test with four questions of increasing difficulty. The remaining five Word files have the missing words, numbers and answers to all questions, including a mark scheme for the test.

This powerpoint shows how rays refract through a glass prism for monochromatic light and white light. Includes normal, angle of deviation and dispersion.

This powerpoint shows how light rays travel through convex and concave lenses. It also shows the formation of images with the object at different distances from each type of lens. As an illustration of the use of a convex lens it includes showing how the camera and the magnifying glass each form an image. Rays are drawn in stages to show all the steps in constructing an accurate ray diagram.

This powerpoint begins by showing how light rays travel through a convex lens and how they form an image… As an illustration of the use of a convex lens it includes showing how the camera and the magnifying glass each form an image. It then goes on to show, step by step, how rays of light travel through an astronomical refracting telescope. It also shows how the angular magnification can be found. The second powerpoint shows how light rays travel tthrough a Cassegrain reflecting telescope. Rays are drawn in stages to show all the steps in constructing an accurate ray diagram.

The object of this PowerPoint is to show how the moving alpha particles are deflected according to how close they come to the gold nucleus. This visualization should help it be remembered by students. Since it is impossible to represent an atom and its nucleus to scale on a diagram, I have kept putting in reminders of this. The first slide explains that the diagram of alpha particle, gold atom and gold nucleus are very much not to scale and the nucleus is about 1/100 000th of the size of the atom. It then shows the deflections of moving alpha particles when they bombard a gold atom. The next slide enables the user to choose, one by one, which alpha particle they want to watch and it leaves a trail behind to show its exact path. For simplicity the gold foil is then represented by a diagram of gold foil only two atoms thick and there is a second reminder that the nuclei are extremely far apart and so the diagram is not to scale. The next slide separately shows most alphas moving straight through the foil and then the decreasing proportion of alphas that are deflected through small angles, large angles, very large angles and one alpha that bounces back. The next slide repeats this but now shows the tracks. The last slide explains how the results of the experiment lead to Rutherford’s conclusion that the atom is mostly empty space and must have a tiny, dense, positively charged nucleus.

The first powerpoint is designed to show how the conduction electrons behave when a metal sphere is charged by induction. Rather than just describing what happens students can clearly see how the electrons move. It shows a metal sphere with positive ions fixed in position and negative conduction electrons. It illustrates how the conduction electrons move when a negative rod is moved towards and away from the sphere. It then shows how the conduction electrons behave when a negative rod is brought close to the sphere which is then briefly connected to earth. The negative rod is then removed, leaving the sphere positively charged. The above is repeated but this time with a positively charged rod which is used to give the sphere a negative charge by induction. The second powerpoint is a simple example of inducing a charge. It shows how electrons are attracted to the top of a tree when a positively charge cloud moves overhead and then return to earth when the cloud moves away.

The first Word Document consists of ten pages of notes on Kinetic Theory with some words, formulas, sketch graphs and questions to be completed by the students. It begins with a recap of pressure, volume, temperature, absolute zero and the Kelvin scale. It goes over the Gas Laws as experimental relationships between p, V, T and mass including the mole, Avogadro constant, molar gas constant, Boltzmann constant, pV = nRT , pV = NkT for N molecules and p1 V1/T1 = p2 V2/T2 followed by some questions. It then moves from the macroscopic behaviour of an ideal gas to the microscopic motion of its molecules beginning with the assumptions needed to make a gas ideal followed by a derivation of pV = 1/3 N m crms2. Next is a section on the internal energy of an ideal gas and the relationship between temperature and molecular kinetic energy including the derivation of 1/2 m crms2 = 3RT/2NA = 3/2 k T. Relative molecular mass and molar mass is then covered, followed by work done by an ideal gas = p delta V. Finally, there are a few questions and a summary of all the formulas that have been derived. The second Word Document has all the answers.

This unit of work consists of four Word documents which require the completion of words, numbers, calculations and graphs. The first document covers the concept of an ideal gas and how its molecules behave. It explains how Brownian motion is supporting evidence for the particle theory. It also explains how the molecules in a gas exert a pressure on the walls of the container. It relates the average speed of the molecules to the temperature of the gas and it recaps the units of pressure and volume. The second document covers the concept of absolute zero, the Kelvin scale and its connection to an ideal gas as well as the conversion between Kelvin and Celsius. It also covers the pressure law, namely the pressure of a fixed mass gas at a constant volume is directly proportional to it temperature in Kelvin and p1/T1 = p2/T2. It includes the Kelvin temperature of a gas is directly proportional to the average kinetic energy of its molecules. This is followed by a few questions on converting between Celsius and Kelvin and the use of p1/T1 = p2/T2 showing how to set out the working. The third document shows how to perform an experiment to give the relationship between the pressure and temperature of a fixed mass of air at constant volume. The students can watch a demonstration, perform the experiment to obtain their own results or they can use the typical results provided to plot a graph which can be extrapolated back to find a value for absolute zero. It also describes the qualitative relationship between pressure and Kelvin temperature for a gas in a sealed container. The fourth document shows how to perform an experiment to give the relationship between the pressure and volume of a fixed mass of air at constant temperature. Both simplified and more realistic results are given so students can draw conclusions and come up with Boyle’s Law, namely the pressure of a fixed mass gas at a constant temperature is inversely proportional to it volume and p1V1 = p2V2. This is followed by a qualitative explanation of why the pressure rises when a gas is squashed and how this relates to inverse proportion. Finally, there are some questions on the use of p1V1 = p2V2 with an emphasis on how to set out the working. The next four Word documents have all the answers.

This powerpoint shows how a ray of light refracts into and out of a parallel sided glass block. Includes normal, angle of incidence and angle of refraction. It also explains why water looks shallower than it really is, including real and apparent depth. (It also shows how spear fishermen will miss a fish if they aim for the image!)

This powerpoint shows how a de-exciting atom emits photons of different wavelengths. It then relates the energy jumps, in eV, to photon wavelengths, in nm, and therefore to their position in the line emission spectrum. It also shows, in animation, how an atom is ecited by collision and by a photon. Lastly it shows, in animation, how a fluorescent tube works. To aid understanding everything is done in stages so that each step can be explained.

This powerpoint shows an object moving in a circle. Its aim is to explain the difficult concept of how an object moving in a circle at constant speed is accelerating. It explains this in terms of changing velocity and in terms of their being a resultant force. It emphasizes that the object is not in equilibrium and there is no outwards force. It shows how an object flies off along the tangent when the centripetal force ceases.

The first file gives the construction of a moving coil loudspeaker and a description of how it works. The second file has the answers to the two missing words. The third file has question which require a knowledge of catapult fields and shows how the coil is forced in and out. The fourth file has the answers to the questions.

This powerpoint shows how rays reflect off a plane mirror. It explains how to draw an accurate ray diagram and image. It includes lateral inversion. Third and last slide shows how Pepper’s Ghost illusion works.

The first file is a test which requires a knowledge and understanding of mass, weight, weight = mg, force diagrams, balanced forces, net force, net force= ma, gravitational field strength and acceleration due to gravity. The second file has the answers and mark scheme.

This powerpoint shows how to find the half-life of a radioisotope from a count-rate, corrected for background, versus time graph. It shows the randomness and the effect of not correcting for background. It also shows how to find the half-life from a number of undecayed nuclei versus time graph.

The first file has student notes which explain why an object moving in a circle at constant speed is accelerating towards the centre of the circle. It goes step by step through this difficult concept. It refers to Newton’s First Law, centripetal force, centripetal acceleration, the definition of velocity and the definition of acceleration. It explains why the velocity changes yet the speed does not change. It gives examples of circular motion and explains the relationship between centripetal force and the mass, speed and radius of orbit of the object. It also relates the speed to the radius of orbit and the time period. There are words to be completed by the student as the teacher explains each step. The third, and last, page has questions designed to check on the understanding of the previous two pages. There is NO reference to the equation F = mv2/r. The second file has the missing words and answers to the questions.

The first file has student notes which cover the force of gravity, orbits and how gravity provides the centripetal force It also shows how the radius of orbit and the speed of the planet are related. It gives information on the planets surrounding the Sun and mentions comets, asteroids, meteors and meteorites. It show how the radius of orbit of a satellite and its speed are related and explains what geostationary and polar obits are as well as giving their different uses. It gives the advantages of having scientific satellites above the earth’s atmosphere and it explains why satellites eventually fall to Earth Lastly it reminds students how the kinetic energy is constant and the momentum is continually changing for an object in orbit at a constant speed. There are a few words to be completed by the student. The second file has the missing words. The third file has a number of questions to check their understanding of the above notes. Students will have to read the notes carefully before answering the questions. The fourth file has the answers to the questions.

This is a work book is a comprehensive introduction to forces. The first file is the front page if you decide to use this resource as booklet. The second file has 10 pages that covers resultant (net) force, equilibrium, friction, mass, weight, gravitational fields, calculation of net force and of weight, balanced and unbalanced forces, force diagrams which includes weight, reaction, tension and friction. It also covers the idea that unbalanced forces cause acceleration and balanced forces mean an object is stationary or moving at constant speed. There are plenty of questions to reinforce the concepts and it briefly touches on electrostatic, magnetic and gravitational fields. It does NOT cover F = ma and terminal velocity. The third file has the answers to all the missing words and calculations.

The first file covers Newtons three laws. It includes the definition of the newton, net force = ma and the relationship between net force, mass and acceleration. There are questions to consolidate understanding. It ends with questions on net force = ma and weight which get progressively harder. The second file has the answers to all the missing words and questions.

The first powerpoint uses rays travelling from glass into air and from water into air to illustrate TIR. Includes critical angle and critical ray. As an example of a use of TIR there is also a slide showing how light totally internally reflects along an optical fibre and illustrates the need for cladding glass. The second powerpoint shows how you can find the critical angle using a semicircular glass block and gives the two conditions necessary for TIR to occur. The third powerpoint is meant to reinforce the concept of TIR. It shows how 45 degree prisms can be used to turn a light ray through 90 degrees and through 180 degrees. A non-45 degree prism is used to further reinforce the concept of TIR. Rays are drawn in stages to show all the steps in constructing an accurate ray diagram.